POST 00299 : VACCINE FREEZING CONTINUED

Post00299 VACCINE FREEZING CONTINUED 16 November 2000 CONTENTS 0. MODERATORS NOTE ON VACCINE FREEZING 1. LOW TEMPERATURE PROTECTION: IN TRANSPORT 2. LOW TEMPERATURE PROTECTION: REFRIGERATORS 3. THE USE OF INDICATORS: THE STOPWATCH 4. OTHER THOUGHTS... The Technet'99 report and presentations are available on the web at: http://www.who.int/vaccines- ccess/Restructuring/Vaccines/Vaccine_Quality/Vaccine_Cold_Chain/Technet/199 9Technet.htm You can also request copies by email to: [[email protected]][email protected][/email] ____________________________________*______________________________________ 0. MODERATORS NOTE ON VACCINE FREEZING The freezing of Hepatitis B, DPT, DT, TT, Td, and HIB vaccines in the cold chain are of concern. While these vaccines are relatively heat stable they are subject to damage by one or more freezing events. Pertussis vaccine may be affected by supercooling. Field data collected in a variety of climates and settings has shown that vaccine freezing events are common occurrences. More than ten years of frequent field observations by experienced consultants suggest that the problem is not a minor inconvenient technical problem BUT IS A LARGE SCALE PROBLEM compromising both the effectiveness of these vaccines and ultimately the credibility of immunization programs and the GAVI initiative. The Technet 1998 report has a section on low temperature protection. It says that WHO will: * Develop and circulate draft specs by end 1998 * Guidelines will be drafted comment by end 1998 * Low temperature protected equipment will be incorporated into the * Performance specs and test procedures * Manufacturers will be invited to produce equipment ____________________________________*______________________________________ 1. LOW TEMPERATURE PROTECTION: IN TRANSPORT In todays posting Jaap Dominicus and Menno Goedhart of MSF, ask what data and experience is available on the safety of vaccine transport in cold countries. On a very positive note, they point out that they are ready to invest in the testing of cold boxes! Contributions, comments and additions please: [[email protected]][email protected][/email] or use your reply button ___________________________________________________________________________ Date: Thu, 12 Oct 2000 13:45:43 +0100 From: [[email protected]][email protected][/email] (Jaap DOMINICUS) Subject: Re: Low Temperature Protection To: Technet Moderator Dear Allan, As we are not completely sure that the transport in cold countries is safe, we - that is MSF-Holland - would like to post this question to the forum: * What data and/or experience is available on this subject? If need be, we are ready to invest in testing cold boxes for low temperatures. Could you post this? Tnx Jaap Dominicus Menno Goedhart ____________________________________*______________________________________ 2. LOW TEMPERATURE PROTECTION: REFRIGERATORS In Technet Post00293, 27 October 2000, and Post00295, 31 October 2000, proposed specifications for incorporating low temperature protection in refrigerators for vaccines was discussed. A number of potential solutions were offered. * In todays posting Hans Everts, WHO/EPI, and Mogens Munck, UNICEF, discuss some potential solutions. * Debbie Kristensen, PATH, points out that there is no global solution: this must be dealt with country by country. * The moderator asks: 1. Who is going to do it? and 2. How is it going to be achieved? Contributions, comments and additions please: [[email protected]][email protected][/email] or use your reply button ___________________________________________________________________________ From: [[email protected]][email protected][/email] Date: Tue, 31 Oct 2000 17:09:23 +0100 Subject: RE: Post00293 FREEZE WATCH INDICATORS, EXPIRY DATES & USE To: Technet Moderator Dear Allan, Within this context it is worth reminding the readers that all manufacturers have been informed that negative temperatures in refrigerating compartments will no longer be tolerated. The deadline is December 2000 and we have already received from several manufacturers the confirmation that they have solved or are about to solve the problem. Although this helps, it is still not the perfect solution. Appliances are tested in a presumed worst case scenario setting with optimum thermostat setting. The optimum setting is not necessarily the maximum setting and there is nothing to prevent somebody in the field to put it at whatever position he/she likes. Solutions would be: a) make sure that on the thermostat scale the optimum setting is highlighted. The risk is that people might use the optimum setting in colder ambient temperatures, when they should really decrease the setting b) block the thermostat button at the optimum setting, making it impossible to go higher. This is however only an option if we are 100% sure the test conditions are really the absolute worst case scenario. c) get rid of manual thermostats all together. This is an option already studied by manufacturers of compression appliances. For gas absorption it is only possible if a battery is added, which would be a huge disadvantage and for kerosene it still does not make any difference. Best regards Hans Everts Technical Officer EPI WHO Geneva Tel: 00 41 22 791 3683 --- From: [[email protected]][email protected][/email] Date: Thu, 02 Nov 2000 16:10:41 +0200 To: Subject: Re:Post00295 VACCINE FREEZING Dear Allan and all Technet members, Enclosed please find my contribution to the on-going discussion of low temperature protection fridges! Regards to everybody! Mogens Munck P.S. From next week I am back in Spain as my one year assignment with UNICEF, Maputo, is over. My e-mail address will then again be [email protected]. ___________________________________________________________________________ 1.11.2000-11-01 To: Allan Bass and all Technet members! Re.: Discussion on low temperature fridges. I agree with Michel, the ball was never picked up, but I believe that it will be picked up - and hopefully successfully - pls. see below! Next, as Soren Spanner says no need to blame WHO, UNICEF, Vestfrost, and not even Electrolux, but only ourselves for not having made the specifications to demand better low protection. Soren suggests better thermostats, and they will surely help. I suggest eliminating altogether the need for having risky sub-zero temperatures in our vaccine fridges in order to freeze ice packs and/or to reconstitute an ice lining after power failure. How to achieve this? By utilizing eutectics, either commercial ones or the Glaubers salts suggested by me in Copenhagen. On my part I have got UNICEF, Maputo to finance a test of Glaubers' salts at the CSIR, Laboratory in Johannesburg. CSIR will not only test the thermal qualities of Glauber's, salts, but also how best to mix huge quantities and fill hundreds, if not thousands of ice packs with this eutectic. The testing will probably start next week. Technet Forum has already last year presented a description of Glaubers salts. The advantage of Glaubers salts is that it is very cheap to procure when buying bulk quantities. I hope that Glaubers salts would be ideal for filling ice packs, while perhaps commercial eutectics with ALL the thermal characteristics inside the temperature range of 2-10 degrees would be most appropriate for forming ice linings. Conclusion: Eutectics could eliminate the need for having dangerous sub- zero temperatures in our vaccine fridges. Regards! Mogens Munck --- From: "Kristensen, Debra" To: "'Allan Bass'" Subject: RE: Freezing vax in 1996 Date: Fri, 27 Oct 2000 13:45:19 -0700 Dear Allan: Cold chain analysis, training, and temperature monitoring (using whatever means are available) are probably the keys to this hidden problem. A magic, global solution is unlikely; we are not going to see a freeze indicator integrated with a VVM in the near future. I think that this issue needs to be tackled on a country-by-country basis. Note: PATH Ukraine hopes to launch a small cold chain study (2-3 Oblasts) this winter with an emphasis on the risk of freezing. All the best, Debbie ____________________________________*______________________________________ 4. USE OF THE STOPWATCH INDICATOR? Freeze indicators are available, though their use is problematical. FreezeWatch Indicators were last discussed in Technet Post00293 Freeze Watch Indicators, Expiry Dates & Use, 27 October 2000. Serge Ganivet, WHO, asks how the Vaccine Monitor Mark, as incorporated in the StopWatch refrigerator monitor should be used! Contributions, comments and additions please: [[email protected]][email protected][/email] or use your reply button ___________________________________________________________________________ Date: Sat, 28 Oct 2000 To: Technet Moderator From: Serge Ganivet Subject: Re: Post00293 FREEZE WATCH INDICATORS, EXPIRY DATES & USE Dear Allan, I don't think it is too complicate to find action when a Freeze watch indicates that a freezing event has occurred. Anthony and yourself give some action which could be taken or done. My concern is more about the Stop Watch Refrigerator Monitor special when the indicators A, B or C becomes blue. For Example, in a health center I install a Stop Watch Monitor in a vaccine refrigerator the 1st sept'00. After few weeks A becomes blue, OPV should be used within 2 months, measles etc. but in October the EPI responsible receives a new stock of vaccines (OPV, Measles, etc.). How can I manage the different stocks of vaccine. It is absolutely not clear for me. Thank you for your contribution, serge ____________________________________*______________________________________ 4. OTHER THOUGHTS... Contributions, comments and additions please: [[email protected]][email protected][/email] or use your reply button ___________________________________________________________________________ Date: Wed, 01 Nov 2000 To: Technet Moderator From: Ian Neering Subject: Re: Post00295 VACCINE FREEZING Here's a couple of lay questions from someone who knows nothing. Can we assume that it's the act of freezing per se rather than low temperatures which causes vaccine damage? If so, why not simply add some antifreeze of appropriate type to the vaccine formulation? I'm sure I'll be bombarded with a dozen good reasons why this can't be done but thought I'd throw in my two cents worth! Ian Neering --- From: [[email protected]][email protected][/email] Date: Fri, 27 Oct 2000 09:37:45 EDT Subject: Vaccine Freezing To: [[email protected]][email protected][/email] Allan, Where does the problem of vaccine freezing occur? Is it mostly in northern countries and is due to cold winters? Or is it in the warm countries and is due to temperature control in the fridge? Thank you, Carl Erickson --- Allan Replies: All of the above and more in all climates! ____________________________________*______________________________________ Selected news item reprinted under the fair use doctrine of international copyright law: http://www4.law.cornell.edu/uscode/17/107.html